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Clinical Observation of the Hot and Humid Compress Therapy of Traditional Chinese Medicine in the Treatment of Qi Stagnation and Blood Stasis Type of Lumbar Disc Herniation
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作者 Hailin Song kui xu +3 位作者 Hong Zhu Zengwu xu Peng Li Runkai Wang 《Open Journal of Orthopedics》 2024年第7期312-324,共13页
Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis,... Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis, clinical evidence is limited. Objective: The purpose of this study is to provide high-quality evidence to support the effectiveness of the traditional Chinese hot and humid compress in the treatment of LDH with qi stagnation and blood stasis. Methods: From October 2021 to November 2023, 86 patients with LDH of qi stagnation and blood stasis type were recruited in our hospital and divided into a control (n = 43) and an observation group (n = 43) according to the random number table method. The control group was given routine clinical treatment, and the observation group was treated with the hot and humid compress therapy for two weeks. The visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, TCM syndrome score, serum interleukin-6 (IL-6), serum interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were observed and compared between the two groups before and after treatment, and the clinical efficacy of the two groups was evaluated. Results: After treatment, the VAS score, TCM symptom score, and serum IL-6, IL-1β, and TNF-α levels decreased in both groups (P P P P P Conclusions: The hot and humid compress of traditional Chinese medicine can effectively relieve pain, restore lumbar function, improve TCM syndromes, reduce the level of inflammatory factors, and have a curative effect in treating LDH. 展开更多
关键词 Chinese Medicine Hot and Humid Compress Lumbar Disc Herniation Qi Stagnation and Blood Stasis Type TCM Symptom Score Clinical Efficacy
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Local buckling failure analysis of high-strength pipelines 被引量:2
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作者 Yan Li Jian Shua +2 位作者 Zhong-Li Jin Ya-Tong Zhao kui xu 《Petroleum Science》 SCIE CAS CSCD 2017年第3期549-559,共11页
Pipelines in geological disaster regions typically suffer the risk of local buckling failure because of slender structure and complex load. This paper is meant to reveal the local buckling behavior of buried pipelines... Pipelines in geological disaster regions typically suffer the risk of local buckling failure because of slender structure and complex load. This paper is meant to reveal the local buckling behavior of buried pipelines with a large diameter and high strength, which are under different conditions, including pure bending and bending combined with internal pressure. Finite element analysis was built according to previous data to study local buckling behavior of pressurized and unpressurized pipes under bending conditions and their differences in local buckling failure modes. In parametric analysis, a series of parameters,including pipe geometrical dimension, pipe material properties and internal pressure, were selected to study their influences on the critical bending moment, critical compressive stress and critical compressive strain of pipes.Especially the hardening exponent of pipe material was introduced to the parameter analysis by using the Ramberg–Osgood constitutive model. Results showed that geometrical dimensions, material and internal pressure can exert similar effects on the critical bending moment and critical compressive stress, which have different, even reverse effects on the critical compressive strain. Based on these analyses, more accurate design models of critical bending moment and critical compressive stress have been proposed for high-strength pipelines under bendingconditions, which provide theoretical methods for highstrength pipeline engineering. 展开更多
关键词 Local buckling High-strength pipeline Finiteelement analysis Critical bending moment Criticalcompressive stress Critical compressive strain
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Secure Transmission in Satellite-UAV Integrated System Against Eavesdropping and Jamming:A Two-Level Stackelberg Game Model 被引量:1
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作者 Chengjian Liao kui xu +3 位作者 Hongpeng Zhu Xiaochen Xia Qiao Su Nan Sha 《China Communications》 SCIE CSCD 2022年第7期53-66,共14页
Aiming at the physical layer security(PLS)secure transmission existing in the information backhaul link of the satellite-UAV integrated(SUI)network,a two-layer Stackelberg game model(TSGM)that can resist full-duplex(F... Aiming at the physical layer security(PLS)secure transmission existing in the information backhaul link of the satellite-UAV integrated(SUI)network,a two-layer Stackelberg game model(TSGM)that can resist full-duplex(FD)eavesdropping and jamming attacks is proposed.The confrontation relationship between the UAV network and the attacker is established as the first layer Stackelberg game.The source UAV adjusts its own transmission power strategy according to the attacker’s jamming strategy to resist malicious jamming attacks.The internal competition and cooperation relationship in UAV network is modeled as the second layer Stackelberg game,and the optimal cooperative UAV transmits jamming signal to the attacker to resist malicious eavesdropping attacks.Aiming at the“selfishness”of UAV nodes,a price incentive mechanism is established to encourage UAV to actively participate in cooperation,so as to maximize the advantages of cooperative communication.For the proposed TSGM,we construct the utility function and analyze the closed equilibrium solution of the game model,and design a three-stage optimal response iterative(TORI)algorithm to solve the game equilibrium.The simulation results show that the proposed TSGM can effectively increase the utility of the source UAV and improve the enthusiasm of cooperation compared with other power control models. 展开更多
关键词 physical layer security secure transmission satellite-UAV system Stackelberg game
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Computational Insights into Charge Storage Mechanisms of Supercapacitors 被引量:2
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作者 kui xu Hui Shao +4 位作者 Zifeng Lin Céline Merlet Guang Feng Jixin Zhu Patrice Simon 《Energy & Environmental Materials》 2020年第3期235-246,共12页
Computational modeling methods,including molecular dynamics(MD)and Monte Carlo(MC)simulations,and density functional theory(DFT),are receiving booming interests for exploring charge storage mechanisms of electrochemic... Computational modeling methods,including molecular dynamics(MD)and Monte Carlo(MC)simulations,and density functional theory(DFT),are receiving booming interests for exploring charge storage mechanisms of electrochemical energy storage devices.These methods can effectively be used to obtain molecular scale local information or provide clear explanations for novel experimental findings that cannot be directly interpreted through experimental investigations.This short review is dedicated to emphasizing recent advances in computational simulation methods for exploring the charge storage mechanisms in typical nanoscale materials,such as nanoporous carbon materials,2 D MXene materials,and metal-organic framework electrodes.Beyond a better understanding of charge storage mechanisms and experimental observations,fast and accurate enough models would be helpful to provide theoretical guidance and experimental basis for the design of new high-performance electrochemical energy storage devices. 展开更多
关键词 2D material charge storage mechanism molecular simulations porous electrode SUPERCAPACITOR
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振荡冲击电压下SF_6气体中绝缘子气隙局部放电特性研究 被引量:2
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作者 黄军凯 杨涛 +1 位作者 许逵 陈仕军 《电力大数据》 2018年第4期37-44,共8页
随着GIS设备现场冲击耐压试验的推广实施,冲击电压下的局部放电检测被作为一种新方法,应用于GIS的现场绝缘诊断。冲击电压能够有效限制电晕稳定性作用,相比交流低频电压对局部极不均匀场类缺陷的发现能力更强,因此该方法将具有较好的应... 随着GIS设备现场冲击耐压试验的推广实施,冲击电压下的局部放电检测被作为一种新方法,应用于GIS的现场绝缘诊断。冲击电压能够有效限制电晕稳定性作用,相比交流低频电压对局部极不均匀场类缺陷的发现能力更强,因此该方法将具有较好的应用前景。本文建立了冲击电压下的局部放电宽频带电脉冲检测系统,采用标准振荡雷电冲击(OLI)和标准振荡操作冲击(OSL)作为激励源,对绝缘子气隙缺陷在SF_6气体中的局部放电特性及影响因素进行了研究,并在此基础上针对预置人工绝缘气隙缺陷的实际GIS试品进行了模拟试验。研究表明:在振荡冲击下,气隙局部放电脉冲主要包括首次放电、后继放电及反向放电三种放电形式,其中首次放电对其他几种放电形式具有决定作用。且气压、背景场强及气隙尺寸比等对绝缘子气隙局部放电行为具有明显影响。GIS的模拟局部放电检测表明,两种振荡冲击电压(OLI和OSI)均能够有效检测GIS内部的气隙类缺陷。 展开更多
关键词 振荡冲击电压 六氟化硫 GIS 局部放电 放电特性
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Power Allocation Optimization for Spectrum-Efficient Multi-Pair Two-Way Massive MIMO Full-Duplex Relay over Ricean Channels
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作者 Chuangyou Wu Tong Yue +1 位作者 kui xu Wei Xie 《International Journal of Communications, Network and System Sciences》 2017年第8期35-47,共13页
In this paper we investigate the power allocation optimization for spectrum efficient multi-pair two-way massive MIMO (TWMM) amplify-and-forward (AF) full-duplex (FD) relay over Ricean fading channels, where multiple ... In this paper we investigate the power allocation optimization for spectrum efficient multi-pair two-way massive MIMO (TWMM) amplify-and-forward (AF) full-duplex (FD) relay over Ricean fading channels, where multiple user-pairs exchange information within pair through a AF-FD relay with very large number of antennas, while each user equipped with a single antenna. First, the zeroforcing reception/zeroforcing transmission and maximum-ratio combining/maximum ratio transmission processing matrices with imperfect channel state information at the relay are presented. Then, the unified asymptotic signal-to-interference-plus-noise ratio (SINR) expression of the system at general power scaling schemes are investigates. Finally, the joint user-relay power allocation (JURPA) scheme is proposed to improve the spectral efficiency of TWMM-AF-FD relay system. Simulation results show that the proposed JURPA scheme outperforms traditional user-side only power allocation scheme. 展开更多
关键词 MASSIVE MIMO Ricean FADING Channels Processing MATRICES Power Allocation
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Secure resource allocation against colluding eavesdropping in a user-centric cell-free massive multiple-input multiple-output system
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作者 Na LI Yuanyuan GAO +4 位作者 kui xu Xiaochen XIA Huazhi HU Yang LI Yueyue ZHANG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2024年第4期500-512,共13页
We investigate the resource allocation problem of a cell-free massive multiple-input multiple-output system under the condition of colluding eavesdropping by multiple passive eavesdroppers.To address the problem of li... We investigate the resource allocation problem of a cell-free massive multiple-input multiple-output system under the condition of colluding eavesdropping by multiple passive eavesdroppers.To address the problem of limited pilot resources,a scheme is proposed to allocate the pilot with the minimum pollution to users based on access point selection and optimize the pilot transmission power to improve the accuracy of channel estimation.Aiming at the secure transmission problem under a colluding eavesdropping environment by multiple passive eavesdroppers,based on the local partial zero-forcing precoding scheme,a transmission power optimization scheme is formulated to maximize the system’s minimum security spectral efficiency.Simulation results show that the proposed scheme can effectively reduce channel estimation error and improve system security. 展开更多
关键词 CELL-FREE Colluding eavesdropping Limited pilot resources Access point selection Security rate
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Rapid Prediction Model for Urban Floods Based on a Light Gradient Boosting Machine Approach and Hydrological–Hydraulic Model 被引量:3
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作者 kui xu Zhentao Han +1 位作者 Hongshi xu Lingling Bin 《International Journal of Disaster Risk Science》 SCIE CSCD 2023年第1期79-97,共19页
Global climate change and sea level rise have led to increased losses from flooding.Accurate prediction of floods is essential to mitigating flood losses in coastal cities.Physically based models cannot satisfy the de... Global climate change and sea level rise have led to increased losses from flooding.Accurate prediction of floods is essential to mitigating flood losses in coastal cities.Physically based models cannot satisfy the demand for real-time prediction for urban flooding due to their computational complexity.In this study,we proposed a hybrid modeling approach for rapid prediction of urban floods,coupling the physically based model with the light gradient boosting machine(LightGBM)model.A hydrological–hydraulic model was used to provide sufficient data for the LightGBM model based on the personal computer storm water management model(PCSWMM).The variables related to rainfall,tide level,and the location of flood points were used as the input for the LightGBM model.To improve the prediction accuracy,the hyperparameters of the LightGBM model are optimized by grid search algorithm and K-fold cross-validation.Taking Haidian Island,Hainan Province,China as a case study,the optimum values of the learning rate,number of estimators,and number of leaves of the LightGBM model are 0.11,450,and 12,respectively.The Nash-Sutcliffe efficiency coefficient(NSE)of the LightGBM model on the test set is 0.9896,indicating that the LightGBM model has reliable predictions and outperforms random forest(RF),extreme gradient boosting(XGBoost),and k-nearest neighbor(KNN).From the LightGBM model,the variables related to tide level were analyzed as the dominant variables for predicting the inundation depth based on the Gini index in the study area.The proposed LightGBM model provides a scientific reference for flood control in coastal cities considering its superior performance and computational efficiency. 展开更多
关键词 China Flood prediction HAINAN Hydrological-hydraulic model Light gradient boosting machine Urban floods
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Deciphering microeukaryotic–bacterial co-occurrence networks in coastal aquaculture ponds
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作者 Xiafei Zheng kui xu +4 位作者 Jonathan Naoum Yingli Lian Bo Wu Zhili He Qingyun Yan 《Marine Life Science & Technology》 SCIE CAS CSCD 2023年第1期44-55,共12页
Microeukaryotes and bacteria are key drivers of primary productivity and nutrient cycling in aquaculture ecosystems.Although their diversity and composition have been widely investigated in aquaculture systems,the co-... Microeukaryotes and bacteria are key drivers of primary productivity and nutrient cycling in aquaculture ecosystems.Although their diversity and composition have been widely investigated in aquaculture systems,the co-occurrence bipartite network between microeukaryotes and bacteria remains poorly understood.This study used the bipartite network analysis of high-throughput sequencing datasets to detect the co-occurrence relationships between microeukaryotes and bacteria in water and sediment from coastal aquaculture ponds.Chlorophyta and fungi were dominant phyla in the microeukaryotic–bacterial bipartite networks in water and sediment,respectively.Chlorophyta also had overrepresented links with bacteria in water.Most microeukaryotes and bacteria were classified as generalists,and tended to have symmetric positive and negative links with bacteria in both water and sediment.However,some microeukaryotes with high density of links showed asymmetric links with bacteria in water.Modularity detection in the bipartite network indicated that four microeukaryotes and twelve uncultured bacteria might be potential keystone taxa among the module connections.Moreover,the microeukaryotic–bacterial bipartite network in sediment harbored significantly more nestedness than that in water.The loss of microeukaryotes and generalists will more likely lead to the collapse of positive co-occurrence relationships between microeukaryotes and bacteria in both water and sediment.This study unveils the topology,dominant taxa,keystone species,and robustness in the microeukaryotic–bacterial bipartite networks in coastal aquaculture ecosystems.These species herein can be applied for further management of ecological services,and such knowledge may also be very useful for the regulation of other eutrophic ecosystems. 展开更多
关键词 Microeukaryote Bipartite network Interactions Keystone taxa NESTEDNESS
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Joint power control and passive beamforming optimization in RIS-assisted anti-jamming communication
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作者 Yang LIU kui xu +3 位作者 Xiaochen XIA Wei XIE Nan MA Jianhui xu 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2023年第12期1791-1802,共12页
Due to the openness of the wireless propagation environment,wireless networks are highly susceptible to malicious jamming,which significantly impacts their legitimate communication performance.This study investigates ... Due to the openness of the wireless propagation environment,wireless networks are highly susceptible to malicious jamming,which significantly impacts their legitimate communication performance.This study investigates a reconfigurable intelligent surface(RIS)assisted anti-jamming communication system.Specifically,the objective is to enhance the system’s anti-jamming performance by optimizing the transmitting power of the base station and the passive beamforming of the RIS.Taking into account the dynamic and unpredictable nature of a smart jammer,the problem of joint optimization of transmitting power and RIS reflection coefficients is modeled as a Markov decision process(MDP).To tackle the complex and coupled decision problem,we propose a learning framework based on the double deep Q-network(DDQN)to improve the system achievable rate and energy efficiency.Unlike most power-domain jamming mitigation methods that require information on the jamming power,the proposed DDQN algorithm is better able to adapt to dynamic and unknown environments without relying on the prior information about jamming power.Finally,simulation results demonstrate that the proposed algorithm outperforms multi-armed bandit(MAB)and deep Q-network(DQN)schemes in terms of the anti-jamming performance and energy efficiency. 展开更多
关键词 Reconfigurable intelligent surface(RIS) Power control ANTI-JAMMING Reinforcement learning(RL)
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基于多流接收空间调制的去蜂窝MIMO下行传输方法
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作者 黄谋华 张冬梅 +2 位作者 许魁 谢威 夏晓晨 《中国科学:信息科学》 CSCD 北大核心 2023年第1期111-127,共17页
将多流接收空间调制(multi-stream receive-spatial modulation,MSR-SM)技术应用于用户和接入点(access point,AP)都是多天线的去蜂窝(cell-free)多输入多输出(multiple-input multiple-output,MIMO)下行链路传输,为绿色节能的无线通信... 将多流接收空间调制(multi-stream receive-spatial modulation,MSR-SM)技术应用于用户和接入点(access point,AP)都是多天线的去蜂窝(cell-free)多输入多输出(multiple-input multiple-output,MIMO)下行链路传输,为绿色节能的无线通信提供新的思路.在AP的最高发射功率和用户的最低信干噪比(signal interference-to-noise ratio,SINR)约束下,运用连续凸逼近(sequential convex approximation,SCA)算法求得每个AP的功率控制系数,实现能量效率(energy efficiency,EE)最优化.为减少不必要的服务AP数量,降低系统总消耗功率,本文提出基于注水(water-filling)算法的接入点选择方案.通过仿真表明,本文所提的功率分配算法相比最大最小(max-min)功率控制算法可以显著提升能量效率,基于多流接收空间调制的下行链路传输模式,其能量效率性能优于传统的空分复用MIMO数字调制模式.此外,基于AP选择方案的连续凸逼近算法相比无AP选择方案的功率控制算法,能够进一步增强能量效率. 展开更多
关键词 去蜂窝 多流接收空间调制 连续凸逼近 能量效率 接入点选择
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A transgene-free method for rapid and efficient generation of precisely edited pigs without monoclonal selection 被引量:10
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作者 kui xu Xiuling Zhang +6 位作者 Zhiguo Liu Jinxue Ruan Changjiang xu Jingjing Che Ziyao Fan Yulian Mu kui Li 《Science China(Life Sciences)》 SCIE CAS CSCD 2022年第8期1535-1546,共12页
Gene-edited pigs for agricultural and biomedical applications are typically generated using somatic cell nuclear transfer(SCNT).However, SCNT requires the use of monoclonal cells as donors, and the time-consuming and ... Gene-edited pigs for agricultural and biomedical applications are typically generated using somatic cell nuclear transfer(SCNT).However, SCNT requires the use of monoclonal cells as donors, and the time-consuming and laborious monoclonal selection process limits the production of large populations of gene-edited animals. Here, we developed a rapid and efficient method named RE-DSRNP(reporter RNA enriched dual-sg RNA/CRISPR-Cas9 ribonucleoproteins) for generating gene-edited donor cells. RE-DSRNP takes advantage of the precise and efficient editing features of dual-sg RNA and the high editing efficiency, low off-target effects, transgene-free nature, and low cytotoxic characteristics of reporter RNA enriched RNPs(CRISPR-Cas9ribonucleoproteins), thus eliminating the need for the selection of monoclonal cells and thereby greatly reducing the generation time of donor cells from 3–4 weeks to 1 week, while also reducing the extent of apoptosis and chromosomal aneuploidy of donor cells. We applied RE-DSRNP to produce cloned pigs bearing a deletion edit of the wild-type p53-induced phosphatase 1(WIP1)gene: among 32 weaned cloned pigs, 31(97%) carried WIP1 edits, and 15(47%) were homozygous for the designed fragment deletion, and no off-target event was detected. The WIP1 knockout(KO) pigs exhibited male reproductive disorders, illustrating the utility of RE-DSRNP for rapidly generating precisely edited animals for functional genomics and disease research. REDSRNP's strong editing performance in a large animal and its marked reduction in the required time for producing SCNT donor cells support its application prospects for rapidly generating populations of transgene-free cloned animals. 展开更多
关键词 dual-sg RNA CRISPR-Cas9 ribonucleoproteins transgene-free without monoclonal selection cloned pig
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Long-term,multidomain analyses to identify the breed and allelic effects in MSTN-edited pigs to overcome lameness and sustainably improve nutritional meat production 被引量:6
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作者 Ziyao Fan Zhiguo Liu +7 位作者 kui xu Tianwen Wu Jinxue Ruan Xinmin Zheng Shideng Bao Yulian Mu Tad Sonstegard kui Li 《Science China(Life Sciences)》 SCIE CAS CSCD 2022年第2期362-375,共14页
Beef and mutton production has been aided by breeding to integrate allelic diversity for myostatin(MSTN),but a lack of diversity in the MSTN germplasm has limited similar advances in pig farming.Moreover,insurmountabl... Beef and mutton production has been aided by breeding to integrate allelic diversity for myostatin(MSTN),but a lack of diversity in the MSTN germplasm has limited similar advances in pig farming.Moreover,insurmountable challenges with congenital lameness and a dearth of data about the impacts of feed conversion,reproduction,and meat quality in MSTN-edited pigs have also currently blocked progress.Here,in a largest-to-date evaluation of multiple MSTN-edited pig populations,we demonstrated a practical alternative edit-site-based solution that overcomes the major production obstacle of hindlimb weakness.We also provide long-term and multidomain datasets for multiple breeds that illustrate how MSTN-editing can sustainably increase the yields of breed-specific lean meat and the levels of desirable lipids without deleteriously affecting feed-conversion rates or litter size.Apart from establishing a new benchmark for the data scale and quality of genome-edited animal production,our study specifically illustrates how gene-editing site selection profoundly impacts the phenotypic outcomes in diverse genetic back-grounds. 展开更多
关键词 MSTN-edited pigs multidomain evaluation genetic background editing strategy
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A Rapid Prediction Model of Urban Flood Inundation in a High-Risk Area Coupling Machine Learning and Numerical Simulation Approaches 被引量:4
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作者 Xingyu Yan kui xu +1 位作者 Wenqiang Feng Jing Chen 《International Journal of Disaster Risk Science》 SCIE CSCD 2021年第6期903-918,共16页
Climate change has led to increasing frequency of sudden extreme heavy rainfall events in cities,resulting in great disaster losses.Therefore,in emergency management,we need to be timely in predicting urban floods.Alt... Climate change has led to increasing frequency of sudden extreme heavy rainfall events in cities,resulting in great disaster losses.Therefore,in emergency management,we need to be timely in predicting urban floods.Although the existing machine learning models can quickly predict the depth of stagnant water,these models only target single points and require large amounts of measured data,which are currently lacking.Although numerical models can accurately simulate and predict such events,it takes a long time to perform the associated calculations,especially two-dimensional large-scale calculations,which cannot meet the needs of emergency management.Therefore,this article proposes a method of coupling neural networks and numerical models that can simulate and identify areas at high risk from urban floods and quickly predict the depth of water accumulation in these areas.Taking a drainage area in Tianjin Municipality,China,as an example,the results show that the simulation accuracy of this method is high,the Nash coefficient is 0.876,and the calculation time is 20 seconds.This method can quickly and accurately simulate the depth of water accumulation in high-risk areas in cities and provide technical support for urban flood emergency management. 展开更多
关键词 Flood inundation Neural networks Numerical simulations Rapid prediction Spatiotemporal prediction China
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原绿球藻对环境胁迫的生理和分子响应机制 被引量:1
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作者 赵立斌 徐魁 +2 位作者 连英丽 颜庆云 贺志理 《微生物学报》 CAS CSCD 北大核心 2021年第5期1143-1159,共17页
原绿球藻(Prochlorococcus)作为海洋丰度最高的浮游植物,对海洋生态系统的物质循环和能量流动起着重要的驱动作用。原绿球藻生长和光合作用活性容易受到环境胁迫的影响,进而影响整个海洋生态系统的稳定性。因此,研究原绿球藻应对环境胁... 原绿球藻(Prochlorococcus)作为海洋丰度最高的浮游植物,对海洋生态系统的物质循环和能量流动起着重要的驱动作用。原绿球藻生长和光合作用活性容易受到环境胁迫的影响,进而影响整个海洋生态系统的稳定性。因此,研究原绿球藻应对环境胁迫的响应机制具有重要的生态意义。原绿球藻主要通过分化出不同的生态型来适应不同光照和营养盐的海洋环境,但仍然会很难快速适应各种突如其来的海洋环境变化。本文从原绿球藻应对环境胁迫的角度,探讨了其生理和分子响应机制的最新研究进展,包括光系统I循环电子传递在光照变化时发挥的重要作用,通过RNA快速响应而调控基因表达应对环境胁迫,以及在辅助异养细菌的保护下应对活性氧的胁迫等。本文也展望了原绿球藻对环境胁迫响应的生理和分子机制的未来研究方向,旨在为原绿球藻抗逆机制的深入研究提供参考。 展开更多
关键词 原绿球藻(Prochlorococcus) 抗逆机制 光系统I 循环电子传递 藻菌共生 调控RNA
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Bifurcation analysis of dual-sidestay landing gear locking performance considering joint clearance 被引量:1
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作者 kui xu Yin YIN +2 位作者 Yixin YANG Hong NIE Xiaohui WEI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第7期209-226,共18页
Sidestay lock mechanism is an important part of landing gear system,and the locking performance can be analyzed based on changes in its stability.However,during numerical continuation analysis of fully-rigid dual-side... Sidestay lock mechanism is an important part of landing gear system,and the locking performance can be analyzed based on changes in its stability.However,during numerical continuation analysis of fully-rigid dual-sidestay landing gear without clearance,it has been found that the appearance of bifurcation points does not necessarily imply that both sidestay links can be locked synchronously.This problem reveals the limitations of fully-rigid model with ideally-articulated in solving dual-sidestay mechanisms with extremely high motion sensitivity.Therefore,this study proposes a bifurcation analysis method for synchronous locking of dual-sidestay landing gears,which takes into consideration the joint clearance.For in-depth analysis of this problem,we initially build kinematic and mechanical models of a landing gear mechanism that consider joint clearance.Then,the models are solved based on continuation.The fundamental causes of synchronous locking are discussed in detail,and the number of bifurcation points is found to be closely related to whether the landing gear is completely locked.Finally,the effects of structural parameters on the synchronous locking are analyzed,and the feasible region of parameters satisfying synchronous locking condition is given,which agrees well with the test results. 展开更多
关键词 BIFURCATION CLEARANCE Dual-sidestay landing gear Numerical continuation Synchronous locking
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